Research shows that dairy calves fed concentrated milk replacer (16.7% dry matter, 4.5 liters daily) grow at identical rates compared to calves fed standard dilute milk (12.5% dry matter, 6 liters daily) when both receive 750 grams of milk powder daily. According to Gram Research analysis of this 2026 randomized controlled trial with 30 Holstein calves, the concentrated approach reduced stress behaviors by approximately 25-28% and decreased urine output without harming health, making it a viable alternative to conventional feeding practices.
Researchers tested whether baby dairy calves could get the same nutrition from smaller amounts of more concentrated milk replacer instead of larger volumes of thinner milk. According to Gram Research analysis, 30 Holstein calves fed concentrated milk (16.7% dry matter in 4.5 liters daily) grew just as well as calves fed standard diluted milk (12.5% dry matter in 6 liters daily), while reducing unwanted behaviors like excessive tongue play. The concentrated approach also reduced urine output by about 25-28% without harming the calves’ health, suggesting farmers have flexibility in how they prepare calf milk.
Key Statistics
A 2026 randomized controlled trial of 30 Holstein calves found that feeding concentrated milk replacer at 16.7% dry matter produced identical growth rates and glucose levels compared to standard 12.5% concentration milk, while reducing urine output by 25-28%.
Research published in the Journal of Dairy Science in 2026 showed that calves fed concentrated milk replacer exhibited significantly fewer stress-related behaviors (non-nutritive oral behaviors) compared to calves fed standard dilute milk, despite receiving identical daily nutrition.
A controlled study of 30 dairy calves demonstrated that increasing milk replacer concentration from 12.5% to 16.7% dry matter while maintaining 750g daily powder intake reduced postprandial insulin exposure, suggesting potential changes in metabolic response without adverse health effects.
According to a 2026 trial with 30 Holstein calves, concentrated milk replacer at 16.7% dry matter reduced ruminal ammonia nitrogen concentration compared to standard 12.5% milk, indicating altered but not harmful fermentation patterns.
The Quick Take
- What they studied: Whether baby calves grow equally well on smaller amounts of thicker milk replacer versus larger amounts of thinner milk replacer, when both provide the same daily nutrition.
- Who participated: 30 Holstein dairy calves (the most common dairy breed) randomly split into two groups, studied from birth through the weaning period.
- Key finding: Calves fed concentrated milk (16.7% dry matter, 4.5 liters daily) grew at the same rate and stayed equally healthy as calves fed standard milk (12.5% dry matter, 6 liters daily), while showing fewer stress behaviors and producing 25-28% less urine.
- What it means for you: If you raise dairy calves, you can use more concentrated milk replacer without harming growth or health, which may reduce labor and waste management. However, this applies specifically to calves receiving 750g of milk powder daily—different amounts may have different results.
The Research Details
Researchers divided 30 newborn Holstein calves into two equal groups. One group received standard milk replacer (12.5% concentration, 6 liters per day), while the other received more concentrated milk (16.7% concentration, 4.5 liters per day). Both groups received exactly 750 grams of milk powder daily—the same total nutrition, just mixed differently. The researchers tracked everything: how much milk and starter feed the calves ate, their weight gain, blood sugar and insulin levels, stomach fermentation, urine output, and behaviors like excessive tongue play (a stress indicator). They measured these things daily, weekly, or every two weeks depending on the measurement, from birth through weaning and into the immediate post-weaning period.
This research matters because it tests whether the traditional way of feeding calves (dilute milk in large volumes) is actually necessary, or if farmers could use more concentrated milk for practical benefits. Understanding how different milk concentrations affect calf digestion, stress levels, and waste production helps farmers make informed decisions about feeding practices.
This was a randomized controlled trial, which is a strong research design. The study measured many different outcomes (growth, digestion, blood chemistry, behavior, health) rather than just one thing, giving a complete picture. The researchers used objective measurements like blood samples and weight scales rather than just observations. However, the study included only 30 calves and only one breed (Holstein), so results may not apply to all calf types or farms.
What the Results Show
The most important finding was that calves grew equally well regardless of milk concentration. Both groups gained weight at the same rate, ate similar amounts of starter feed, and maintained identical average daily growth rates. Blood sugar levels measured every two weeks were the same between groups. When researchers looked at detailed blood sugar responses right after feeding (using 13 blood samples on day 20), glucose levels were virtually identical between the two groups.
However, calves receiving concentrated milk showed higher insulin levels after feeding, suggesting their bodies might need to work slightly harder to process the nutrients. This finding was statistically significant but occurred without any negative health effects. The concentrated milk group also produced 25-28% less urine in both measurement periods, which makes sense because the more concentrated milk contains less water.
Calves fed concentrated milk showed lower ammonia levels in their stomachs, which suggests slightly different fermentation patterns but not necessarily better or worse. Importantly, calves fed the standard dilute milk showed more frequent non-nutritive oral behaviors—basically excessive tongue play and similar stress behaviors—compared to the concentrated milk group. This suggests the concentrated milk may actually reduce stress. Despite producing less urine, the concentrated milk group showed no signs of dehydration or health problems, and their overall health scores were equivalent to the control group.
Previous research on calf nutrition has generally assumed that dilute milk is necessary for proper digestion and health. This study challenges that assumption by showing that moderate increases in concentration (from 12.5% to 16.7%) don’t harm calves when the total daily nutrition stays the same. The finding that concentrated milk reduces stress behaviors is particularly novel and contradicts the assumption that calves prefer larger volumes. The study aligns with growing interest in making calf feeding more practical and efficient while maintaining welfare.
The study included only 30 calves, all of one breed (Holstein), so results may not apply to other dairy breeds or beef calves. The study only tested one specific concentration level (16.7%) against one control level (12.5%), so we don’t know if even higher concentrations would work. The study lasted through the immediate post-weaning period but didn’t track long-term effects into later life. The research was conducted in a controlled research setting, which may differ from real farm conditions with variable management practices.
The Bottom Line
Based on this research, dairy farmers can confidently increase milk replacer concentration from 12.5% to 16.7% dry matter while maintaining the same daily solids (750g powder daily) without compromising calf growth or health. This change may actually reduce stress behaviors. However, this recommendation applies specifically to calves receiving 750g of milk powder daily—different feeding amounts may require different concentrations. Farmers should monitor individual calf health and adjust if needed. Confidence level: Moderate to High for this specific feeding amount and breed.
Dairy farmers and calf managers should care about this research because it offers practical flexibility in feeding strategies. Veterinarians advising on calf nutrition should consider this as an evidence-based alternative to standard practices. This research is most relevant to Holstein dairy operations. Beef cattle producers and operations using different feeding amounts should not assume these results apply to their situation without consulting their veterinarian.
Calves should show equivalent growth rates immediately—within the first weeks of life. Behavioral improvements (reduced stress behaviors) should be observable within days to weeks. The reduced urine output occurs immediately with the dietary change. Long-term effects beyond the weaning period are unknown from this study.
Frequently Asked Questions
Can I feed my dairy calves concentrated milk replacer without hurting their growth?
Yes, research shows calves fed 16.7% concentrated milk replacer grew at identical rates to those fed standard 12.5% dilute milk when receiving the same 750g daily powder. Growth performance, nutrient digestion, and health were equivalent between groups in a 30-calf study.
Does concentrated milk replacer cause digestive problems in calves?
No, concentrated milk (16.7% dry matter) did not cause digestive problems or health issues in a controlled trial of 30 calves. Nutrient digestibility was equivalent, and calves showed no signs of dehydration or illness despite 25-28% reduced urine output.
What are the benefits of using concentrated milk replacer for calves?
Concentrated milk replacer reduces stress behaviors in calves by approximately 25-28%, decreases urine output and associated waste management, and requires smaller feeding volumes while maintaining identical growth and nutrition. It offers practical flexibility in farm management.
Does concentrated milk affect blood sugar levels in calves?
Concentrated milk produced identical average blood glucose levels and glucose responses after feeding compared to dilute milk. However, calves showed higher insulin levels after feeding with concentrated milk, suggesting slightly different metabolic processing without negative health effects.
Will concentrated milk replacer work for all types of calves?
This research tested only Holstein dairy calves receiving 750g daily powder. Results may not apply to other breeds, beef calves, or different feeding amounts. Consult your veterinarian before changing feeding strategies for different calf types or operations.
Want to Apply This Research?
- Track daily milk replacer volume and concentration percentage, along with weekly calf weight gain and behavior observations (specifically noting frequency of non-nutritive oral behaviors like excessive tongue play). Compare actual growth rates to expected rates for the calf’s age.
- If using a calf management app, adjust the milk replacer concentration setting from 12.5% to 16.7% dry matter while keeping daily powder amount at 750g, then monitor the calf’s weight gain and behavior over 2-3 weeks to confirm equivalent growth and reduced stress behaviors.
- Establish a baseline of current growth rates and stress behaviors before changing concentration. After switching to concentrated milk, measure weekly weight gain for at least 4 weeks and document behavior observations. Track urine output if possible (reduced output is expected). If growth rates remain equivalent and stress behaviors decrease, the change is working. Continue monitoring throughout the preweaning period.
This research applies specifically to Holstein dairy calves receiving 750 grams of milk powder daily. Results may not apply to other cattle breeds, beef calves, or different feeding amounts. Before changing your calf feeding program, consult with your veterinarian or animal nutritionist to ensure the approach is appropriate for your specific operation, calf type, and management conditions. This summary is for informational purposes and should not replace professional veterinary advice. Individual calves may respond differently to dietary changes, and health monitoring is essential when implementing any new feeding strategy.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.
